RFID is a communication technology in which RFID tags may be associated with (e.g., placed on or inside of, affixed to, packaged with) objects and remotely queried, tracked and/or identified using radio frequency waves. An RFID query device may emit radio frequency waves to which RFID tags may respond. Some RFID tags may be considered “active” because they operate under their own power. Other RFID tags may be considered “passive” because they do not have their own power source and instead are powered by a signal received from an RFID query device. In either case, an RFID tag may receive the radio frequency waves emitted by the RFID query device and may respond thereto.
An RFID query device may be any device that includes one or more components to exchange RFID query signals with one or more RFID tags. A non-exclusive list of devices that may function as RFID query devices includes mobile telephones, smart phones, portable computers, scanners, entryway devices (e.g., to read name badges with RFID tags), cameras, other portable electronic devices, and so forth.
Near Field Communication (“NFC”) is a subset of RFID that limits the range of communications to a close range. NFC may be useful for applications where potentially sensitive data is exchanged between an RFID query device and an RFID tag, such as credit card and passport applications. Longer range applications of RFID may be useful in other applications where data exchanged is not sensitive and/or where RFID tags are likely to be distanced from an RFID query device, such as for animal tracking. Unless otherwise indicated, the term RFID as used herein encompasses NFC.